I'm sorry I can't answer your question directly, as I do not own an Amilo XI2550 and I'm not familiar with its layout and innards.
I'd recommend that you put this question directly to the attention of Fujitsu Siemens Support Team which you can
reach via this site:
http://ts.fujitsu.com/support/ I assume though that you do not need the HDD Door Assembly, since your notebook should originally be fitted with this cover anyway.
Also, I suspect that
41 34007439 UWL:83GP75508-00 BRACKET 2ND HDD NV and
41 38003877 UWL:40GP7502C-10 BRACKET 2ND HDD NV
refer to the two-part HDD holder, which keeps the HDD fixed in its place inside the laptop. Actually, this bracket isn't really "needed" for the HD to function properly. It just makes sure that the hard drive can not inadvertently slip out of the SATA connector.
As far as the two cables are concerned, it could be the case that these are already inside your laptop at the RAID controller board.
Have you already opened up the laptop and had a peek with regard to what's inside of the second HD tray?
What I could gather from another thread in this forum about a similar model (XI 2528)
topic,26557,-Hinweise-zur-Nachruestung-2-HD-Amilo-XI2528.htmlthese different parts are really inexpensive, so it wouldn't hurt your budget if you ordered everything except the HDD door assembly, just to be on the safe side.
Hope I could at least be of some kind of help to you.
Edit: according to this thread here
topic,28237,-Wo-ist-die-zweite-Festplatte.htmlthe notebook should be pre-equipped with the Raid controller and the neccessary cables.
So you would only need the two brackets.
But then again, I can not assure that the same holds true for the Russian models.